PIK3CA, encoding the catalytic subunit p110alpha of phosphatidylinositol 3-kinase (PI3K), is activated in malignant diseases. However, the role of the PIK3CA gene aberrations for tumourigenesis of head and neck squamous cell carcinoma (HNSCC) is to date unclear. The present study was designed to determine the genomic aberration of PIK3CA in invasive HNSCC and dysplastic precursor lesions by fluorescence in situ hybridization (FISH) with a YAC probe, containing the PIK3CA gene, on isolated interphase nuclei from histomorphologically well-defined regions of formalin-fixed tissue sections and to compare these data with protein and mRNA expression of p110alpha. The mRNA and protein levels of p110alpha were assessed, respectively, by in situ hybridization and immunohistochemistry on consecutive tissue sections. Copy number gains at 3q26 were observed in one of six low-to-moderate dysplasias (17%) and in seven of nine high-grade dysplasias (78%), as well as in 11 carcinomas (100%). In addition, one of seven high-grade dysplasias (14%) and 6 of 11 carcinomas (55%) had amplifications of 3q26. The majority of cases with copy number gain in more than 50% of the cells and/or amplification in more than 10% of cells showed increased p110alpha mRNA and protein expression, whereas only two cases (18%) (one high-grade dysplasia and one carcinoma) with no gain or low-level gain displayed increased p110alpha protein expression. These data suggest that 3q26 copy number gain and amplification represent early genomic aberrations in HNSCC carcinogenesis. In addition, p110alpha mRNA and protein expression in HNSCC may be regulated by these genomic aberrations as well as by epigenetic events.

Nine acinar cell carcinomas of the pancreas, 2 pancreatoblastomas, 16 solid-cystic (papillary-cystic) tumors, and 20 ductal adenocarcinomas were immunocytochemically investigated using antisera against four pancreatic enzymes (alpha-amylase, lipase, trypsinogen, chymotrypsinogen), four pancreatic hormones, neuron specific enolase (NSE), alpha-1-antitrypsin (AAT), carcinoembryonic antigen (CEA), and CA 19-9. Lipase, trypsinogen, and chymotrypsinogen, but no alpha-amylase were detected in all acinar cell carcinomas and pancreatoblastomas. In contrast, solid-cystic tumors (SCT) were negative for pancreatic enzymes but 2 of 16 stained with NSE. No neuroendocrine granules or pancreatic hormones could be demonstrated. AAT was found in all tumors except ductal adenocarcinomas, which stained with CEA and CA 19-9. The study established pancreatic enzymes (except alpha-amylase) as immunocytochemical markers for acinar cell carcinomas and pancreatoblastomas. There is as yet no marker specific for SCT, which would elucidate the obscure histogenetic origin and phenotypic differentiation of these tumors.

Primary cardiac angiosarcomas are rare tumors with unfavorable prognosis. Pathogenic driver mutations are largely unknown. We therefore analyzed a collection of cases for genomic aberrations using SNP arrays and targeted next-generation sequencing (tNGS) of oncogenes and tumor-suppressor genes. Recurrent gains of chromosome 1q and a small region of chromosome 4 encompassing KDR and KIT were identified by SNP array analysis. Repeatedly mutated genes identified by tNGS were KDR with different nonsynonymous mutations, MLL2 with different nonsense mutations, and PLCG1 with a recurrent nonsynonymous mutation (R707Q) in the highly conserved autoinhibitory SH2 domain in three of 10 cases. PLCg1 is usually activated by Y783 phosphorylation and activates protein kinase C and Ca 2þ -dependent second messengers, with effects on cellular proliferation, migration, and invasiveness. Ectopic expression of the PLCg1-R707Q mutant in endothelial cells revealed reduced PLCg1-Y783 phosphorylation with concomitant increased c-RAF/MEK/ ERK1/2 phosphorylation, increased IP3 amounts, and increased Ca 2þ -dependent calcineurin activation compared with ectopic expressed PLCg1-wild-type. Furthermore, cofilin, whose activation is associated with actin skeleton reorganization, showed decreased phosphorylation, and thus activation after expression of PLCg1-R707Q compared with PLCg1-wild-type. At the cellular level, expression of PLCg1-R707Q in endothelial cells had no influence on proliferation rate, but increased apoptosis resistance and migration and invasiveness in in vitro assays. Together, these findings indicate that the PLCg1-R707Q mutation causes constitutive activation of PLCg1 and may represent an alternative way of activation of KDR/PLCg1 signaling besides KDR activation in angiosarcomas, with implications for VEGF/KDR targeted therapies. Cancer Res; 74(21); 6173-83. Ó2014 AACR.

Human papillomavirus (HPV)-related squamous cell carcinoma of the oropharynx (OSCC) are clinical and biological distinct from their HPV-unrelated counterparts. Patients with HPV-related OSCC display improved prognosis and therefore we investigated possible immune cell infiltrations associated with this tumor phenotype. We retrospectively analyzed a randomly selected cohort of 140 OSCC for presence of immune cells and HPV by immunohistochemistry and PCR followed by beadbased hybridization (Luminex technology). HPV prevalence was 24.3% as determined by positive staining of p16INK4a and detection of high risk HPV-DNA. We found significantly higher numbers of CD56 positive (CD561) cells in tumor and surrounding microenvironment in HPV-associated compared to HPV-negative OSCC (t-test: p 5 0.004 and p 5 0.002). For the entire cohort presence of CD561 cells was associated with increased overall survival independent from HPV (Kaplan-Meier: p 5 0.002; Cox regression: p 5 0.042). Presence of CD561 cells also correlated with a better outcome in HPV-negative and especially in HPV-negative OSCC with alcohol consumption 2 standard drinks per day (Kaplan-Meier: p 5 0.05 and p 5 0.003). Immunofluorescence localization of granular Granzyme B (GZMB) within CD561 cells and coexpression of CD16 and CD56 suggests that detected CD561 cells mainly represent cytotoxic Natural Killer (NK) cells. The fraction of potentially cytotoxic NK cells was significantly higher in HPV-associated compared to HPV-negative OSCC (Mann-Whitney-U-Test: p 5 0.011). The elevated abundance and activity of cytotoxic NK cells in OSCC with HPV driven carcinogenesis might contribute to favorable outcome in HPV-related OSCC.Head and neck cancer (HNC, comprising cancers of the oral cavity, lip, pharynx, nasopharynx and larynx) is ranking at position seven of newly diagnosed cancers and cause of cancer death worldwide, with 4.8% of total cancer incidence and 4.6% of total cancer mortality. 1 In particular oropharyngeal squamous cell carcinomas (OSCC) are related to high risk human papillomavirus (HPV) infection, which is accepted to be causally connected to HNC. 2,3 A recently published metaanalysis demonstrates a rising incidence of HPV1 OSCC in the United States from 21% (pre-1990), to 51% (1990-1999), to 65% (2000-2013). 4 Patients with HPV-associated OSCC show lower levels of disease recurrence and progression compared to patients with HPV-negative OSCC. Even with good loco regional tumor control, patients with HPV-associated OSCC have similar rates of distant metastases as patients with HPVnegative OSCC. Further efforts are needed to understand clinical and biological features of this distinct disease. 2,5,6 Molecular basis of HPV-associated cancers differ from their HPVunrelated counterparts. 3 Pathways related to cell cycle control or apoptosis (commonly affected by mutations in HPVnegative cancers) are silenced at protein level by HPVoncoproteins (mainly E6 and E7). It has been speculated that lower levels of genetic alterations contribute to better treat...

Autofluorescence endoscopy facilitates the detection and delineation of precancerous lesions, carcinoma in situ, and microinvasive cancer of the larynx more accurately than clinical observation alone. Scarring, marked hyperkeratosis, and inflammation can limit the predictive value of the method.